addiction genes Flashcards
DRD2 dopamine gene
The DRD2 gene is a dopamine gene.
Individuals with an A1 variation of the DRD2 gene have fewer dopamine receptors (D2).
This means less pleasure is experienced in the nucleus accumbens when taking part in activities such as eating and sex,
so the addict has to overcompensate in order to gain satisfaction.
Comings et al (1996) found that 48.7% of smokers and ex-smokers carried the A1 variant of the DRD2 gene compared with 25.9% of the general population.
Similar results were again found by Comings et al (1996) in gamblers - 50.9% of gamblers carried the A1 variant of the DRD2 gene in comparison with 25.9% of non-addicts.
Alcohol metabolism, alcoholism and genetics
Drinking heavily puts people at risk for many adverse health consequences, including alcoholism, liver damage and various cancers. However, some people appear to be at greater risk than others for developing these problems. Why do some people drink more than others? And why do some people who drink develop problems, whereas others do not?
Research shows that alcohol-related problems are influenced by individual variations in alcohol metabolism (the way in which alcohol is broken down and eliminated by the body). Alcohol metabolism is controlled by genetic factors, such as variations in the enzymes that break down alcohol. Differences in alcohol metabolism may put some people at greater risk for alcohol problems whereas others may be somewhat protected from alcohol’s harmful effects due to their genetic make-up.
genetic explanation evaluation
continue the following; using PEEL
one strength of the genetic explanation for addiction is that it explains why some people are more likely to become addicted than others.
- this can reduce the amount of blame placed on addicts because with the reason being a biological one; they cannot control their addiction
-the issue with this however, is that if an individual sees their addiction as an unstoppable consequence of their genetic makeup, they may be less likely to take responsibility for their own recovery.
- This can prove important when the individual is battling to overcome their addiction.
genetic explanation evaluation
continue the following; using PEEL
Kendler and Prescott (1998) interviewed almost 2,000 twins.
-they found that, although enviornmental and social factors influenced whether a person would initiate cocaine use, genes affected whether the person became addicted or not.
-the concordance rate for cocaine initiation in MZ twins was 54% compared to 42% in DZ twins.
However, the concordance rate for addiction to cocaine was 35% in MZ and 0% in DZ twins.
- This suggests that genetic factors have a large part to play in the maintenance of addiction.
genetic explanation evaluation
continue the following; using PEEL
Kendler et al (2012) conducted a large scale adoption study in sweden
-they found that chidlren of biological parents or who had genetic full and half siblings who had a drug addiction had a significantly higher risk of drug addiction themselves.
-however, they also noted that the risk was much higher if there were enviornmental factors in the adopted family such as criminal activity, divorce, alcohol problems or death.
-this siggests that although genes play a role in addicition, enviornmental factors are equally as important
